Electronic device for detecting object proximity and controlling a display

ABSTRACT

An electronic device comprises: a motion detector configured to detect motion of the electronic device; a proximity detector configured to detect proximity of an object to the electronic device; a display unit; a memory; and at least one processor that function as: a control unit configured to control display preparatory processing for performing display on the display unit so as to start in response to predetermined motion of the electronic device being detected based on motion detected by the motion detector; and a display control unit configured to control display so as to be performed on the display unit in response to proximity of an object being detected by the proximity detector.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to an electronic device provided with adisplay device, a control method for the same, and a storage medium.

Description of the Related Art

There are known electronic devices provided with a display device thatdetect the proximity of a user based on detection information from aproximity detection sensor (e.g., motion sensor) or the like built intothe display device and control operations of the display device.Japanese Patent Laid-Open No. 2008-252526 discloses a televisionreceiver that powers on the device, in the case where it is judged bylight detection unit and human detection unit that lighting in the roomis on and there is a person present. Also, Japanese Patent Laid-Open No.2001-339627 discloses an image capturing apparatus that is provided withan EVF (Electronic Viewfinder) and has an eye-on detection mechanismthat powers on a display device in the case where it is detected by alight sensor that an eye is up close to the viewfinder. Such an eye-ondetection mechanism enables power consumption to be reduced by poweringoff the display device in the case where the user does not have his orher eye up close.

Incidentally, while a display device generally requires that a pluralityof types of voltages (driving voltages), namely, a positive voltage anda negative voltage, are applied (generated) in order to drive a displayelement, it is desirable, from the viewpoint of suppressing powerconsumption, to stop generation of the driving voltages if a user is notin proximity. In this regard, there is a problem in that since thedisplay device requires enough time for the driving voltages tostabilize after stepping up or stepping down for generating the drivingvoltages has been completed, display cannot be performed immediatelyupon a user moving into proximity when generation of the drivingvoltages is stopped.

SUMMARY OF THE INVENTION

The present invention has been made in consideration of theaforementioned problems, and realizes, in an electronic device thatdetects proximity of a user and controls display, shortening of thedisplay start time when proximity is detected.

In order to solve the aforementioned problems, one aspect of the presentinvention provides an electronic device comprising: a motion detectorconfigured to detect motion of the electronic device; a proximitydetector configured to detect proximity of an object to the electronicdevice; a display unit; a memory; and at least one processor thatfunction as: a control unit configured to control display preparatoryprocessing for performing display on the display unit so as to start inresponse to predetermined motion of the electronic device being detectedbased on motion detected by the motion detector; and a display controlunit configured to control display so as to be performed on the displayunit in response to proximity of an object being detected by theproximity detector.

Another aspect of the present invention provides, a control method foran electronic device having a motion detection unit configured to detectmotion of an electronic device, a proximity detection unit configured todetect proximity of an object to the electronic device and a displayunit, the control method comprising: controlling display preparatoryprocessing for performing display on the display unit so as to start inresponse to predetermined motion of the electronic device being detectedbased on motion detected by the motion detection unit; and controllingdisplay so as to be performed on the display unit in response toproximity of an object being detected by the proximity detection unit.

Still another aspect of the present invention provides, a non-transitorycomputer-readable storage medium storing a program for causing acomputer to execute a control method of an electronic device having amotion detection unit configured to detect motion of an electronicdevice, a proximity detection unit configured to detect proximity of anobject to the electronic device and a display unit, the control methodcomprising: controlling display preparatory processing for performingdisplay on the display unit so as to start in response to predeterminedmotion of the electronic device being detected based on motion detectedby the motion detection unit; and controlling display so as to beperformed on the display unit in response to proximity of an objectbeing detected by the proximity detection unit.

According to the present invention, it becomes possible, in anelectronic device that detects proximity of a user and controls display,to shorten the display start time when proximity is detected.

Further features of the present invention will become apparent from thefollowing description of exemplary embodiments (with reference to theattached drawings).

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of the specification, illustrate embodiments of the invention, andtogether with the description, serve to explain the principles of theinvention.

FIG. 1 is a back perspective view of a digital camera serving as anexample of an electronic device according to an embodiment.

FIG. 2 is a block diagram showing an exemplary functional configurationof a digital camera according to the embodiment.

FIG. 3 is a block diagram showing an exemplary functional configurationof a proximity detection unit according to the embodiment.

FIG. 4 is a block diagram showing an exemplary functional configurationof an EVF driving unit according to the embodiment.

FIGS. 5A and 5B are flowcharts showing operations of a series of displaycontrol processing that uses display preparatory processing according tothe embodiment.

FIG. 6 is a diagram illustrating operating states of an EVF and adisplay unit resulting from display control processing that uses displaypreparatory processing of the embodiment.

FIG. 7 is a diagram illustrating attitude detection informationgenerated by an attitude detection unit when a user carries out aneye-on shooting preparatory operation.

DESCRIPTION OF THE EMBODIMENTS

Configuration of Digital Camera 100

Hereinafter, preferred embodiments of the present invention will bedescribed with reference to the drawings. FIG. 1 shows a backperspective view of a digital camera 100 serving as an example of anapparatus to which the present invention is applicable. In FIG. 1, adisplay unit 28 is a display unit that displays images and various typesof information and is provided on a back surface of the camera. Ashutter button 61 is an operation unit for issuing a shootinginstruction. A mode selection switch 60 is an operation member forswitching between various modes. A power switch 72 is an operationmember that switches power supply of the digital camera 100 on and off.An electronic dial 73 is included in an operation unit 70, and is arotational operation member that enables operations such as moving theselected frame and advancing images. An arrow key 74 is included in theoperation unit 70, and is an arrow key (4-direction key) whose up, down,left and right portions can be respectively pressed. Operations thatdepend on the portion of the arrow key 74 that is pressed are possible.A SET button 75 is included in the operation unit 70, and is a pushbutton that is mainly used to set selected items. An LV button 76 isincluded in the operation unit 70, and is a button for switching liveview (hereinafter, LV) on and off on a menu screen. In a moving imageshooting mode, the LV button 76 is used to instruct starting andstopping of moving image shooting (recording). An enlargement button 77is included in the operation unit 70, and is an operation button forturning an enlargement mode on and off and changing a magnificationratio during live view display in a shooting mode. In a playback mode,the enlargement button 77 functions as an enlargement button forenlarging a playback image and increasing the magnification ratio. Areduction button 78 is included in the operation unit 70, and is abutton for decreasing the magnification ratio of an expanded playbackimage and reducing a displayed image. A playback button 79 is includedin the operation unit 70, and is an operation button for switchingbetween the shooting mode and the playback mode. Pressing the playbackbutton 79 during the shooting mode transitions to the playback mode,enabling the most recent image among the images recorded on a recordingmedium 200 to be displayed on the display unit 28. An eye-on viewfinder16 is a look-through viewfinder that enables an EVF 105 to be viewed viaan eyepiece unit. A lid 202 is the lid of a slot that houses therecording medium 200. A proximity detection unit 104 includes aproximity sensor, and detects the proximity of an object such as a faceto the proximity detection unit 104.

FIG. 2 is a block diagram showing an exemplary configuration of thedigital camera 100 according to the present embodiment.

In FIG. 2, a taking lens 103 is a lens group including a zoom lens and afocusing lens. A shutter 101 is a shutter that is provided with anaperture function. An image capturing unit 22 is an image sensor that isconstituted by a CCD sensor, a CMOS sensor or the like that convertsoptical images into electrical signals. The A/D convertor 23 converts ananalog signal into a digital signal. The A/D convertor 23 is used inorder to convert the analog signal that is output from the imagecapturing unit 22 into a digital signal. A barrier 102, by covering animage capturing system of the digital camera 100 that includes thetaking lens 103, prevents the image capturing system including thetaking lens 103, the shutter 101 and the image capturing unit 22 fromcontamination and damage.

An image processing unit 24 performs resize processing, such aspredetermined pixel interpolation and reduction, and color conversionprocessing on data from the A/D convertor 23 or data from a memorycontrol unit 15. Also, the image processing unit 24 performspredetermined computational processing using captured image data, and asystem control unit 50 performs exposure control and ranging controlbased on the obtained computation result. AF (auto focus) processing, AE(auto exposure) processing, and EF (electronic flash) processing thatemploy a TTL (through-the-lens) system are thereby performed. The imageprocessing unit 24 further performs predetermined computationalprocessing using captured image data, and also performs AWB (automaticwhite balance) processing employing the TTL system based on the obtainedcomputation result.

Output data from the A/D convertor 23 is written to a memory 32 directlyvia the memory control unit 15 or via the image processing unit 24 andthe memory control unit 15. The memory 32 stores image data obtained bythe image capturing unit 22 and converted into digital data by the A/Dconvertor 23, and image data for displaying on the display unit 28. Thememory 32 is provided with sufficient storage capacity to store apredetermined number of still images and moving images and audio of apredetermined length.

Also, the memory 32 doubles as a memory for image display (videomemory). A D/A converter 13 converts data for image display that isstored in the memory 32 into an analog signal, and supplies the analogsignal to the display unit 28. Image data for display written in thememory 32 is thus displayed by the display unit 28 via the D/A converter13. The display unit 28 performs display that depends on the analogsignal from the D/A converter 13 on a display such as an LCD serving asa display monitor. Digital signals obtained through A/D conversion bythe A/D convertor 23 and stored in the memory 32 undergo analogconversion in the D/A converter 13 and are sequentially transferred tothe display unit 28 to enable through image display (live view display).The display unit 28 is provided with a touch panel over the entiresurface of the display, and is able to accept touch operations from theuser on a menu screen displayed on the display.

A D/A converter 14 converts data for image display that is stored in thememory 32 into an analog signal, and supplies the analog signal to theEVF 105. The EVF 105 is provided with a display device that isconstituted by an organic EL display, a liquid crystal display or thelike, for example, within the viewfinder 16. In the case where thedisplay device is an organic EL display, for example, the display deviceincorporates an organic EL panel employing a thin-film transistoractive-matrix drive system. One display element of the organic EL panelis constituted by three RGB organic EL elements, and emits light as aresult of a voltage being applied to the organic EL elements. In the EVF105, the voltage that is applied to each organic EL element by an EVFdriving unit 112 is adjusted to control the light emission amount ofeach color, enabling a desired image to be tonally displayed. Data forimage display that is stored in the memory 32 is displayed when the userlooks through the viewfinder 16, and live view display is realized. Thedisplay unit 28 and the EVF 105 are capable of menu screen display,image file display, live view display and the like, in response toinstructions of the system control unit 50. The display unit 28 and theEVF 105 are able to perform on/off control of each display independentlythrough the operation unit 70.

The EVF driving unit 112 includes a drive circuit that supplies a drivetiming signal for driving the EVF 105, and includes a step-up unit and astep-down unit for generating driving voltages of the EVF 105. The EVFdriving unit 112 generates various driving voltages, and applies thegenerated driving voltages to the EVF 105 in synchronization with thedrive timing signal. The proximity detection unit 104 includes aninfrared light emitting body and a light receiving circuit, and detectswhether an object is in a prescribed position, by emitting infraredlight at a fixed interval and measuring the amount of light reflected bythe object. The proximity detection unit 104, by being disposed in thevicinity of the EVF 105, functions as an eye-on detection unit thatdetect that the user is looking through the viewfinder 16 and that hisor her eye is on the eyepiece unit of the viewfinder 16. The proximitydetection unit 104 is capable of detecting the distance to the user withdetection threshold values over a plurality of levels. The systemcontrol unit 50, upon acquiring proximity detection information that isoutput from the proximity detection unit 104, stops display of thedisplay unit 28 and starts display of the EVF 105.

A nonvolatile memory 56 is a memory serving as a recording medium thatis electrically erasable and recordable, and an EEPROM or the like isused, for example. Constants for use in operations of the system controlunit 50, programs and the like are stored in the nonvolatile memory 56.The programs referred to here are computer programs for executingvarious flowcharts which will be discussed later in the presentembodiment.

The system control unit 50 is a control unit having at least oneprocessor, and performs overall control of the digital camera 100. Byexecuting the aforementioned programs recorded in the nonvolatile memory56, various processing of the present embodiment which will be discussedlater is realized. A RAM is used for a system memory 52. Constants andvariables for use in operations of the system control unit 50, programsread out from the nonvolatile memory 56 and the like are expanded in thesystem memory 52. The system control unit 50 also performs displaycontrol by controlling the memory 32, the D/A converter 13, the displayunit 28 and the like.

A system timer 53 is a clocking unit for measuring time that is used invarious controls and the time of an internal clock.

The mode selection switch 60, the shutter button 61 and the operationunit 70 are operation unit for inputting various types of operatinginstructions to the system control unit 50.

The mode selection switch 60 switches the operating mode of the systemcontrol unit 50 to one of a still image recording mode, the moving imageshooting mode, the playback mode, and the like. The still imagerecording mode includes an auto shooting mode, an auto scenediscrimination mode, a manual mode, an aperture priority mode (Av mode),and a shutter speed priority mode (Tv mode). Also, there are variousscene modes that serve as shooting-scene specific shooting settings, aprogrammed AE mode, a custom mode, and the like. Any of these modes aredirectly switched to with the mode selection switch 60. Alternatively,after initially switching to a list screen of shooting modes with themode selection switch 60, one of the plurality of displayed modes may beselected, and the selected mode may then be switched to using anotheroperation member. Similarly, a plurality of modes may also be includedin the moving image shooting mode.

A first shutter switch 62 turns on when the shutter button 61 providedin the digital camera 100 is partially operated, that is, with aso-called half press (shooting preparation instruction), and produces afirst shutter switch signal SW1. As a result of the first shutter switchsignal SW1, the operations of AF (autofocus) processing, AE (automaticexposure) processing, AWB (automatic white balance) processing, EF(electronic flash) processing and the like are started.

A second shutter switch 64 turns on when the shutter button 61 is fullyoperated, that is, with a so-called full press (shooting instruction),and produces a second shutter switch signal SW2. As a result of thesecond shutter switch signal SW2, the system control unit 50 starts theoperations of a series of shooting processing from signal readout fromthe image capturing unit 22 to writing of image data to the recordingmedium 200.

As a result of an operation such as selection of various function iconsthat are displayed on the display unit 28 being performed, the operationmembers of the operation unit 70 are appropriately allocated a functionfor each scene and acts as various function buttons. The functionbuttons include an end button, a back button, an image advance button, ajump button, a stop-down button and an attribute modification button,for example. For example, a settable menu screen is displayed on thedisplay unit 28 when a menu button is pressed. The user is able tointuitively perform various settings using the menu screen displayed onthe display unit 28, the 4-direction (up, down, left, right) button andthe set button.

A power supply control unit 80 is constituted by a battery detectorcircuit, a DC-DC converter, a switch circuit that switches the block tobe electrified and the like, and detects whether or not a battery ismounted, the type of battery, and the remaining battery charge. Also,the power supply control unit 80 controls the DC-DC converter based onthese detection results and instructions from the system control unit50, and supplies a required voltage to units including the recordingmedium 200 for a required period.

A power supply unit 30 consists of a primary battery such as an alkalinebattery and a lithium battery, a secondary battery such as a NiCdbattery, a NiMH battery and a Li ion battery, an AC/DC adaptor, and thelike. A recording medium I/F 18 is an interface with the recordingmedium 200 which is a memory card, a hard disk or the like. Therecording medium 200 is a recording medium such as a memory card forrecording captured images, and is constituted by a semiconductor memory,an optical disk, a magnetic disk or the like.

A communication unit 54 is connected wirelessly or by cable, andtransmits and receives video signals, audio signals and the like. Thecommunication unit 54 is also capable of connecting to a wireless LAN(Local Area Network) and the Internet. The communication unit 54 iscapable of transmitting images (including through images) captured bythe image capturing unit 22 and images recorded on the recording medium200, and is able to receive image data and other various informationfrom an external device.

An attitude detection unit 55 includes an acceleration sensor or agyroscope sensor, for example, and detects the attitude of the digitalcamera 100 with respect to the gravitational direction. The attitudedetection unit 55 is able to output the acceleration of each componentof three axes (X, Y, Z), and is thus able to detect the motion of thedigital camera 100, based on the acceleration detected by the attitudedetection unit 55. Note that, in the present embodiment, a 3-axiscoordinate system is adopted as shown in FIG. 1. That is, the X-axis isin the horizontal direction (right-left direction), as seen from theback surface of the digital camera 100, with the right side as seen fromthe back surface being the positive direction. Also, the Y-axis is inthe vertical direction (up-down direction) of the digital camera 100,with the direction of gravity, that is, the down side being the positivedirection of the Y-axis. Furthermore, the Z-axis is in the front-backdirection of the digital camera 100, with the backside being thepositive direction. A characteristic of the acceleration output of theattitude detection unit 55 is that the X-axis and Y-axis components ofgravitational acceleration change in a range of −1.0 g to 1.0 g when thedigital camera is rotated in a roll direction (about the Z-axis), forexample. In the case where the digital camera 100 is rotated in the rolldirection, the Z-axis component will constantly be 0 g, since the Z-axisdirection is not affected by changes in gravitational acceleration. Notethat the characteristics of acceleration that are detected in the eye-onshooting preparatory operation, which will be discussed later, will bediscussed later. Also, by using the detection result of the attitudedetection unit 55, it is distinguishable whether the image captured bythe image capturing unit 22 is an image captured with the digital camera100 held vertically or an image captured with the digital camera 100held horizontally. The system control unit 50 is able to add directioninformation that depends on the attitude detected by the attitudedetection unit 55 to an image file of the image captured with the imagecapturing unit 22 or to rotate and record the image.

Configuration of Proximity Detection Unit 104

Next, an exemplary functional configuration of the proximity detectionunit 104 will be described, with reference to FIG. 3.

An external interface 301 is an external interface of the proximitydetection unit 104, and performs transmission of control signals to theproximity detection unit 104 by the system control unit 50, notificationof proximity detection results from the proximity detection unit 104 tothe system control unit 50, and the like.

A light emitting element control unit 302 converts the forward currentof an infrared light emitting element 303 to a constant current. Also,the amount of light emission of the infrared light emitting element 303can be controlled by increasing or decreasing the forward current of theinfrared light emitting element 303. The infrared light emitting element303 irradiates an object 309 which is a physical object with light of alight amount associated with the current controlled by the lightemitting element control unit 302, through an infrared light emittinglens window 304 a. Note that, the object 309 is, in the example of thepresent embodiment, the face or part of the body of a user of thedigital camera 100.

A logic control unit 305 includes a predetermined control circuit, andcontrols the various parts of the proximity detection unit 104. Thelogic control unit 305 controls the lighting/extinguishing timing of theinfrared light emitting element 303, and the store/reset timing of alight receiving element 306. Also, the logic control unit 305 is able toset detection threshold values over a plurality of levels with respectto the output value from an A/D conversion unit 307, and is thus able todetect the proximity distance to the object 309 in a stepwise manner.The logic control unit 305 notifies the determination result of whetheror not the detection threshold value was exceeded to the system controlunit 50 through the external interface 301.

The light receiving element 306 receives light irradiated by theinfrared light emitting lens window 304 a that has been reflected by theobject 309 and collected by a light receiving lens window 304 b,performs photoelectric conversion thereon, and outputs an analog signal.An amplification unit 308 amplifies the analog signal output from thelight receiving element 306, and outputs the resultant signal to the A/Dconversion unit 307. The A/D conversion unit 307 converts the analogsignal output from the amplification unit 308 into a digital signal.

Configuration of EVF Driving Unit 112

Next, an exemplary functional configuration of the EVF driving unit 112will be described, with reference to FIG. 4. The EVF driving unit 112shown in FIG. 4 is constituted by an EVF control unit 401 and an EVFpower supply unit 402. The EVF control unit 401 supplies an EVF controlsignal for driving the EVF 105 to the EVF 105 based on an EVF drivingunit control signal from the system control unit 50, for example, andsupplies a power supply timing signal for driving the EVF 105 to the EVFpower supply unit 402. The EVF power supply unit 402 generates apredetermined driving voltage for driving the EVF 105, based on theinput power supply from the power supply unit 30. The EVF power supplyunit 402 is a step-up unit and a step-down unit such as a DC-DCconverter that generates a predetermined driving voltage. The EVF powersupply unit 402 generates the driving voltage in synchronization withthe power supply timing signal that is output from the EVF control unit401, and applies the generated driving voltage to the EVF 105. Notethat, at the time of the EVF power supply unit 402 generating apredetermined driving voltage, there is a risk that inrush current willoccur when power is suddenly input, and the input power that is suppliedwill shut down. Thus, the EVF power supply unit 402, in the case ofgenerating a predetermined driving voltage, suppresses the occurrence ofinrush current by starting power supply gradually after the power supplytiming signal is input. In this way, since the EVF power supply unit 402starts power supply gradually, a predetermined amount of time will berequired at the time of generating a predetermined driving voltage.

Series of operations related to display control processing using displaypreparatory processing

Next, a series of operations related to display control processing usingdisplay preparatory processing for performing display on the EVF of thedigital camera 100 will be described, with reference to FIGS. 5A and 5B.FIGS. 5A and 5B are flowcharts showing an image capturing operation inthe present embodiment. Note that this processing is realized by aprogram recorded on the nonvolatile memory 56 being read out to thesystem memory 52 and the read program being executed by the systemcontrol unit 50. Also, this processing is started by the digital camera100 starting up when the power switch 72 is turned on by a user, forexample.

In step S501, the system control unit 50 starts up the attitudedetection unit 55 and the proximity detection unit 104. In step S502,the system control unit 50 acquires attitude detection informationrepresenting the attitude of the digital camera 100 detected by theattitude detection unit 55, and performs computational processing on theacquired attitude detection information. The system control unit 50determines whether the user is carrying out an eye-on shootingpreparatory operation, using this computational processing. As will bediscussed later with FIG. 6, in the case of the user carrying out aneye-on shooting preparatory operation (e.g., the user bringing thedigital camera up to his or her face), the user moves the digital camera100 quickly, in order to perform eye-on shooting from carrying out amanual operation or live view shooting. A large change in accelerationthus occurs in the vertical direction (up-down direction) or horizontaldirection (left-right direction) of the digital camera 100.

The attitude detection information (e.g., change in acceleration thatoccurs in the digital camera 100) generated by the attitude detectionunit when the user carries out an eye-on shooting preparatory operationwill be described, with reference to FIG. 7. FIG. 7 shows the change inthe output of the attitude detection unit 55 when the user transitionsthe digital camera 100 from carrying out a manual operation toperforming eye-on shooting, as an example of an eye-on shootingpreparatory operation. Since the user, when carrying out a manualoperation, is looking at the display unit 28 with the body of thedigital camera 100 at an angle, the Z-axis component of accelerationwill be approximately −0.9 g, for example, in the range of area (1) inFIG. 7 indicating that a manual operation is being carried out.Furthermore, when the user swings the digital camera 100 up from thisstate in order to bring the digital camera 100 up to his or her eye, thestate of acceleration changes, as shown in area (2) of FIG. 7. In thisexample, the Z-axis component of acceleration changes from approximately−1.0 g to about 0 g, and the Y-axis component of acceleration changesfrom approximately 0.5 g to approximately 1.0 g at the same time. Thisindicates that, since the user carries out an operation of quicklypulling the digital camera 100 closer in the front-back direction at thesame time as swinging the digital camera 100 up, the Z-axis component ofacceleration temporarily exhibits a change over 0 g (i.e., plus/minus ofacceleration in the front/back direction is reversed). Also, since theuser does not move the digital camera much in the horizontal directionin the eye-on shooting preparatory operation, the X-axis component ofacceleration exhibits substantially zero in all of areas (1) to (3). Thesystem control unit 50 determines that the user eye-on shootingpreparatory operation has been detected, in the case where the attitudedetection unit 55 detects this change in acceleration. And since theuser will subsequently be in the eye-on state, the Y-axis component ofacceleration will be approximately 1.0 g, as shown in the area (3) ofFIG. 7.

For example, the system control unit 50 determines that an eye-onshooting preparatory operation has been detected, in the case where eachcomponent of the acceleration that is output from the attitude detectionunit 55 satisfies the following conditions, for example. For example, aneye-on shooting preparatory operation is detected, in the case where theZ-axis component of acceleration reverses from a negative to a positivevalue, the Y-axis component changes to greater than or equal to apredetermined threshold value (about 0.3 g) within a predeterminedperiod that includes the point in time of the reversal (e.g., 1500 msbefore, 1000 msec after), and the X-axis component changes within apredetermined width (about 0.2 g).

In step S503, the system control unit 50 determines whether an eye-onshooting preparatory operation was detected from the computation resultof step S502. The system control unit 50 proceeds to step S504 if it isdetermined that an eye-on shooting preparatory operation was detected,and proceeds to step S506 if this is not the case.

In step S504, the system control unit 50 starts an EVF step-upoperation, in order to generate a driving voltage of the EVF 105.Specifically, the system control unit 50 transmits an EVF driving unitcontrol signal for generating the driving voltage of the EVF 105 to theEVF driving unit 112. At this time, the EVF control unit 401 of the EVFdriving unit 112 supplies the power supply timing signal for driving theEVF 105 to the EVF power supply unit 402, and the EVF power supply unit402 starts generation of the driving voltage for driving the EVF 105, inresponse to the power supply timing signal. The system control unit 50continues the display of the display unit 28 at this time. Note that, inthe present embodiment, the abovementioned EVF step-up operationcorresponds to display preparatory processing for controlling thedisplay of the EVF 105.

In step S505, the system control unit 50 determines whether proximity ofan object was detected by the proximity detection unit 104 within a T1time period. At this time, T1 represents the amount of time fromtransitioning to the eye-on shooting preparatory operation until eye-on,for example, and is set to around 1 s. The system control unit 50determines that proximity of an object was detected within the T1 timeperiod clocked by the system timer 53, in the case where an outputindicating proximity of an object by the proximity detection unit 104(indicating that an object is closer than a predetermined proximitythreshold value) is obtained within the T1 time period. The systemcontrol unit 50 proceeds to step S507 if it is determined that proximityof an object was detected within the T1 time period, and proceeds tostep S512 if this is not the case.

In step S506, the system control unit 50 determines whether proximity ofan object was detected by the proximity detection unit 104. The systemcontrol unit 50 proceeds to step S507 if it is determined that proximityof an object was detected, based on the detection result of theproximity detection unit 104, and proceeds to step S513 if this is notthe case.

In step S507, the system control unit 50 starts the display operation ofthe EVF 105, and stops the display operation on the display unit 28 andthe drive power supply generation operation. At this time, display ofthe EVF 105 is performed faster in the case where the EVF step-upoperation is started or continued by the operation of step S504 or stepS509 which will be discussed later, than in the case where the EVFstep-up operation is not performed (in the case of passing via stepS506). That is, since generation of the driving voltage of the EVFrequires a fixed amount of time as mentioned above, display of the EVFcan be performed faster in the case where the EVF step-up operation isstarted in advance after detection of the eye-on shooting preparatoryoperation, than in the case where the EVF step-up operation is startedafter eye-on is detected. On the other hand, in the case where displayof the EVF 105 is performed via step S506, the EVF 105 is displayedafter starting the display preparatory processing at the point in timeof step S507.

In step S508, the system control unit 50 determines whether eye-off wasdetected from the detection result of the proximity detection unit 104.The system control unit 50 determines that eye-off was detected in thecase where a detection result indicating that the object is further awaythan a predetermined proximity threshold value is obtained. The systemcontrol unit 50 proceeds to step S509 if it is determined that eye-offwas detected, and proceeds to step S508 in order to again wait todetermine whether eye-off was detected if this is not the case.

In step S509, the system control unit 50 stops the display operation ofthe EVF 105, and continues the driving voltage generation operation.That is, the EVF control unit 401 stops the display operation of the EVFwith an EVF control signal, but controls the EVF power supply unit 402to continue generating the EVF driving voltage for the EVF 105. On theother hand, the system control unit 50 resumes the display operation ofthe display unit 28 and the drive power supply generation operation.

In step S510, the system control unit 50 determines whether proximity ofan object was detected by the proximity detection unit 104 within a T2time period. T2 represents the amount of time from when the user takeshis or her eye off the EVF until when eye-on shooting is again performedafter carrying out post-shooting preview confirmation, and is set toabout 4 s. The system control unit 50 determines that an object wasdetected within the T2 time period that is clocked by the system timer53, in the case where proximity is detected by the proximity detectionunit 104 within the T2 time period. The system control unit 50 returnsto step S507 and repeats the abovementioned processing, if it isdetermined that proximity of an object was detected within the T2 timeperiod. If this is not the case, the system control unit 50 proceeds tostep S511.

In step S511, the system control unit 50 stops the EVF step-up operationof the EVF 105, and proceeds step S513. This is so that it can be judgedthat the user has not taken his or her eye off the EVF in order to carryout post-shooting preview confirmation, in the case where proximity isnot detected by the proximity detection unit 104 within the T2 timeperiod.

On the other hand, if it is determined in step S505 that proximity of anobject not was detected within the T1 time period, the system controlunit 50, in step S512, stops the EVF step-up operation of the EVF 105.This is because it is conceivable that the eye-on shooting preparatoryoperation in step S503 was erroneously detected in the case whereproximity is not detected by the proximity detection unit 104 within theT1 time period.

In step S513, the system control unit 50 determines whether the powerswitch 72 is turned off. The system control unit 50 returns to step S502and performs the same processing, if it is determined that the powerswitch 72 is not turned off, based on the signal of the power switch 72.On the other hand, if it is determined that the power switch 72 isturned off, the power supply of the digital camera 100 is subsequentlyturned off, and the present series of operations ends.

Exemplary EVF Display Using Display Preparatory Processing

Exemplary EVF display using the abovementioned display preparatoryprocessing will be further described, with reference to FIG. 6. Morespecifically, an example in which the EVF display switching time periodis shortened by starting the EVF step-up operation (i.e., displaypreparatory processing) of the EVF 105 in response to an eye-on shootingpreparatory operation being detected in step S503 will be described.

As shown in (1) of FIG. 6, it is assumed that, in an initial statebefore eye-on shooting, the user is carrying out a manual operation (orlive view shooting). In (1) of FIG. 6, an image is displayed on thedisplay unit 28, but the step-up operation in the EVF 105 has not yetstarted.

From this state, as shown in (2) of FIG. 6, the user makes an upswinging movement in order to transition from carrying out a manualoperation to performing eye-on shooting. At this time, the change in theacceleration described above with reference to FIG. 7 occurs in thedigital camera 100. In (2) of FIG. 6, since the EVF step-up operation ofthe EVF 105 is started in response to the shooting preparatory operationbeing detected, the step-up circuit is driven in the EVF 105. On theother hand, the display unit 28 continues displaying an image.

Furthermore, eye-on is detected in (3) of FIG. 6. By starting the EVFstep-up operation of the EVF 105 in (2) of FIG. 6 (i.e., prior to eye-onbeing detected by the proximity detection unit 104), display switchingto the EVF 105 can be performed faster when the proximity state shown in(3) of FIG. 6 is detected.

As described above, in the present embodiment, the step-up operation(display preparatory processing) of the EVF 105 is started in responseto an eye-on shooting preparatory operation being detected, and displayof the EVF 105 is subsequently performed in response to proximity of anobject being detected. This enables the display start time of the EVF105 after eye-on of the user is detected to be shortened, and displayswitching between the EVF 105 and the display unit 28 to be performedfaster.

Note that, although description of the present embodiment is given,taking an electronic device constituting two display units, namely, theEVF 105 and the display unit 28, as an example, the mode of the displayunit is not limited thereto. That is, the abovementioned embodiment canbe applied to any electronic device that uses at least one EVF. Thisalso applies to a configuration having three or more display unitsincluding an EVF.

Also, although the present embodiment describes an example in whichproximity of an object is detected using infrared projecting/receivinglight as an example of the proximity detection unit 104, other methodssuch as a method of detecting with electrostatic capacity or an imagecapturing apparatus may be used.

Furthermore, although the present embodiment describes an example inwhich the attitude of the digital camera is detected with anacceleration sensor as an example of the attitude detection unit 55,other methods such as a method of detecting attitude using a gyroscopesensor may be used.

Also, the present embodiment describes an example in which transitionfrom carrying out a manual operation to performing eye-on shooting isdetected, as an example of the eye-on shooting preparatory operation.However, the eye-on shooting preparatory operation is not limitedthereto. For example, a configuration may be adopted in which anotheroperation involving swinging the electronic device up to on the eye froma predetermined operation state, such as an eye-on shooting preparatoryoperation from a live view shooting operation, is detected using theattitude detection unit 55.

Furthermore, although the present embodiment describes an example inwhich the system control unit 50 detects an eye-on shooting preparatoryoperation based on attitude detection information that is detected bythe attitude detection unit 55, the attitude detection unit 55 maydetect an eye-on shooting preparatory operation based on attitudedetection information relating to itself. In this case, the systemcontrol unit 50 starts display preparation, in response to an eye-onshooting preparatory operation being detected by the attitude detectionunit 55.

Also, although the present embodiment describes an example in which thedigital camera 100 with a built-in taking lens is used, it is alsonaturally possible to apply the present embodiment to an interchangeablelens digital camera. In this case, a configuration may be adopted inwhich the condition for determining an eye-on shooting preparatoryoperation is changed according to the type of interchangeable lens(taking lens) mounted to a lens mounting unit. In this case, it sufficesto change the condition of the change in acceleration that is applied inthe case where an eye-on shooting preparatory operation is carried out,according to whether the mounted lens is heavy or light.

Note that the various abovementioned controls described as beingperformed by the system control unit 50 may be performed by one piece ofhardware, or overall control of the device may be performed by pluralpieces of hardware sharing the processing.

Also, although the present invention has been described in detail basedon preferred embodiments thereof, the invention is not limited to thesespecific embodiments, and various modes in a range that does not departfrom the spirit of the invention are also embraced therein. Furthermore,the aforementioned embodiments are merely illustrative of the invention,and it is also possible to appropriately combine the embodiments.

Also, although description of the aforementioned embodiments was given,taking the case where the present invention is applied to a digitalcamera as an example, the invention is not limited to this example, andis applicable to any portable device having a display unit for viewingimages in an eye-on state. That is, the present invention is applicableto glasses-type mobile terminals, goggle-type AR and VR terminals,goggle-type information terminals, game devices, medical equipment andthe like.

Other Embodiments

Embodiment(s) of the present invention can also be realized by acomputer of a system or apparatus that reads out and executes computerexecutable instructions (e.g., one or more programs) recorded on astorage medium (which may also be referred to more fully as a‘non-transitory computer-readable storage medium’) to perform thefunctions of one or more of the above-described embodiment(s) and/orthat includes one or more circuits (e.g., application specificintegrated circuit (ASIC)) for performing the functions of one or moreof the above-described embodiment(s), and by a method performed by thecomputer of the system or apparatus by, for example, reading out andexecuting the computer executable instructions from the storage mediumto perform the functions of one or more of the above-describedembodiment(s) and/or controlling the one or more circuits to perform thefunctions of one or more of the above-described embodiment(s). Thecomputer may comprise one or more processors (e.g., central processingunit (CPU), micro processing unit (MPU)) and may include a network ofseparate computers or separate processors to read out and execute thecomputer executable instructions. The computer executable instructionsmay be provided to the computer, for example, from a network or thestorage medium. The storage medium may include, for example, one or moreof a hard disk, a random-access memory (RAM), a read only memory (ROM),a storage of distributed computing systems, an optical disk (such as acompact disc (CD), digital versatile disc (DVD), or Blu-ray Disc (BD)™),a flash memory device, a memory card, and the like.

While the present invention has been described with reference toexemplary embodiments, it is to be understood that the invention is notlimited to the disclosed exemplary embodiments. The scope of thefollowing claims is to be accorded the broadest interpretation so as toencompass all such modifications and equivalent structures andfunctions.

This application claims the benefit of Japanese Patent Application No.2017-127828, filed Jun. 29, 2017, which is hereby incorporated byreference herein in its entirety.

What is claimed is:
 1. An electronic device comprising: a motiondetector configured to detect motion of the electronic device; aproximity detector configured to detect proximity of an object to theelectronic device; a display; a memory; and at least one processor thatfunction as: a control unit configured to control display preparatoryprocessing for performing display on the display so as to start inresponse to predetermined motion of the electronic device being detectedbased on motion detected by the motion detector; and a display controlunit configured to control display so as to be performed on the displayin response to proximity of an object being detected by the proximitydetector, wherein the predetermined motion is detected, in a case wheremotion in which acceleration in a vertical direction of the electronicdevice changes by greater than or equal to a threshold value andacceleration in a horizontal direction of the electronic device changeswithin a predetermined width is detected by the motion detector, withina predetermined period that includes a point in time at which positiveand negative of acceleration in a front-back direction of the electronicdevice is reversed.
 2. The electronic device according to claim 1,wherein the control unit controls the display preparatory processing forperforming display on the display so as to start in response toproximity of an object being detected by the proximity detector withoutdetecting the predetermined motion, and then the display control unitcontrols display so as to be performed on the display.
 3. The electronicdevice according to claim 1, wherein the predetermined motion is motionbringing the electronic device close to a face.
 4. The electronic deviceaccording to claim 1, wherein the display is visible via an eyepieceunit of a viewfinder, wherein the proximity detector functions as aneye-on detection unit configured to detect an eye being on the eyepieceunit, and wherein the predetermined motion is motion involving a usermoving the electronic device in order to have an eye be on the eyepieceunit.
 5. The electronic device according to claim 4, further comprisinga display monitor provided externally to the viewfinder, wherein thepredetermined motion is motion involving the user moving the electronicdevice in order to have eye be on the eyepiece unit from a state ofviewing the display monitor.
 6. The electronic device according to claim5, wherein the display control unit continues display on the displaymonitor when the display preparatory processing is started, and stopsdisplay on the display monitor in response to display being performed onthe display.
 7. The electronic d according to claim 1, wherein thedisplay preparatory processing is processing for generating a drivingvoltage for driving the display.
 8. The electronic device according toclaim 7, wherein, in the processing for generating the driving voltage,power supply is started gradually in order to suppress occurrence of aninrush current, after a power supply timing signal is input.
 9. Theelectronic device according to claim 1, wherein a condition fordetermining that the predetermined motion has occurred changes accordingto a type of interchangeable lens mounted to a lens mounting unit. 10.The electronic device according to claim 1, wherein the electronicdevice is an image capturing apparatus having an image capturing unit.11. A control method for an electronic device having a motion detectorconfigured to detect motion of an electronic device, a proximitydetector configured to detect proximity of an object to the electronicdevice and a display, the control method comprising: controlling displaypreparatory processing for performing display on the display so as tostart in response to predetermined motion of the electronic device beingdetected based on motion detected by the motion detector; controllingdisplay so as to be performed on the display in response to proximity ofan object being detected by the proximity detector, and detect n thepredetermined motion, in a case where motion in which acceleration in avertical direction of the electronic device changes by greater than orequal to a threshold value and acceleration in a horizontal direction ofthe electronic device changes within a predetermined width is detectedby the motion detector, within a predetermined period that includes topoint in time at which positive and negative of acceleration in a frontback direction of the electronic device is reversed.
 12. Anon-transitory computer-readable storage medium storing a program forcausing a computer to execute a control method of an electronic devicehaving a motion detector configured to detect motion of an electronicdevice, a proximity detector configured to detect proximity of an objectto the electronic device and a display, the control method comprising:controlling display preparatory processing for performing display on thedisplay so as to start in response to predetermined motion of theelectronic device being detected based on motion detected by the motiondetector; controlling display so as to be performed on the display inresponse to proximity of an object being detected by the proximitydetector, and detecting the predetermined motion, in a case where motionin which acceleration in a vertical direction of the electronic devicechanges by greater than or equal to a threshold value and accelerationin a horizontal direction of the electronic device changes within apredetermined width detected by the motion detector, within apredetermined period that includes a point in time at which positive andnegative of acceleration in a front -back direction of the electronicdevice is reversed.
 13. An electronic device comprising: a motiondetector configured to detect motion of the electronic device; aproximity detector configured to detect proximity of an object to theelectronic device; a display; a memory; and at least one processor thatfunction as: a control unit configured to control display preparatoryprocessing for performing display on the display so as to start inresponse to predetermined motion of the electronic device being detectedbased on motion detected by the motion detector; and a display controlunit configured to control display so as to be performed on the displayin response to proximity of an object being detected by the proximitydetector, wherein a condition for determining that the predeterminedmotion has occurred changes according to a type of interchangeable lensmounted to a lens mounting unit.
 14. A control method for an electronicdevice having a motion detector configured to detect motion of anelectronic device, a proximity detector configured to detect proximityof an object to the electronic device and a display, the control methodcomprising; controlling display preparatory processing for performingdisplay on the display so as to start in response to predeterminedmotion of the electronic device being detected based on ,notion detectedby the motion detector; and controlling display so as to be performed onthe display in response to proximity of an object being detected by theproximity detector, wherein a condition for determining that thepredetermined motion has occurred changes according to a type ofinterchangeable lens mounted to a lens mounting unit.
 15. Anon-transitory computer-readable storage medium storing a program forcausing a computer to execute a control method of an electronic devicehaving a mono detector configured to detect motion of an electronicdevice, a proximity detector configured to detect proximity of an objectto the electronic device and a display, the control method comprising:controlling display preparatory processing for performing display on,the display to as to start in response to predetermined motion of theelectronic device being detected based on motion detected by the motiondetector; and controlling display so as to be performed on the displayin response to proximity of an object being detected by the proximitydetector, wherein a condition for determining that the predeterminedmotion has occurred changes according to a type of interchangeable lensmounted to a lens mounting unit.